The present invention is directed to method and apparatus for forming a trench drain and, more specifically, to method and apparatus for forming a trench drain including a removable form, two side rails and a plurality of cross members spanning the side rails for improved stability and alignment and ease of installation.
Trench drains have been used in construction for centuries. In modern times, trench drains have been used to collect runoff water and channel it to other locations preventing flooding. Trench drains also provide chemical spill control by preventing chemical spills from escaping into the environment.
Parking lots, airport runways, loading docks, shop floors and other large cement or asphalt areas typically include spaced apart trench drains cover by metal grates. A typical trench drain may be 24 inches deep by 12 inches wide, and may be hundreds or even thousands of feet in length. Opposing ends of a trench drain are disposed at different altitudes to facilitate liquid flow. A conventional trench drain may drop 1 inch in altitude for every 8 feet in length.
A trench drain is typically covered by a metal grate having openings which permit the flow of water into the trench drain while the grate is sufficient to support the weight of vehicles moving across the grate. The grate is supported by the upper edges of the trench drain such that the upper surface of the grate is substantially level with the upper surface of the surrounding cement or asphalt to facilitate persons and vehicles passing over the grate. Typically, the grate is mounted onto frame rails that are installed during or after the formation of the trench. The mounting holes may serve a function during trench fabrication as well.
Several conventional trench drain designs have been used. A trench drain may be formed in place using plywood to make both a bottom form and side forms, which must be removed after concrete is applied and set adjacent the forms. This construction method is time consuming and requires a carpenter to build the forms. Alternatively, some trench drains are made of precast concrete, which are extremely bulky and require heavy equipment to lower them into place. Because of their weights, they can be dangerous during placement and can cause serious injury or death. They must be transported by tractor trailers or similar method to the job sites because of their bulk. The precast forms require significant shipping costs.
Styrofoam forms are a relatively recent alternative product to enter the market. They are comprised of solid foam that is cut into the shape of a trench drain, use elongated steel members and supports to hold them prior to concrete encasement. They are comprised of solid foam forms that are cut to the shape of the basin desired, and use steel frame rails and supports to suspend them prior to concrete encasement. Foam forms are expensive to ship due to relatively large bulk in comparison to little weight. They are susceptible to damage in transit and expensive compared to wood forming techniques. In addition, styrofoam is flammable and can give off toxic gases. It is susceptible to breaking into small pieces during use and is easily scattered in outdoor applications. The material is increasingly regulated by government agencies. Also, some landfills do not accept styrofoam because it will not naturally decompose. In light of the above discussion, styrofoam is an undesirable material for use in forming trench drains.
Recently, various types of apparatus for forming trench drains have been proposed. One proposed solution includes the use of a removable form composed of polystyrene. This solution suffers from the discussed inherent weaknesses of styrofoam. Further, cross-supports used to assist in alignment are disposed below the level of the concrete. Hardware used to secure the cross-supports would likely be encased in concrete. Any attempt to commercially practice this solution would require timely and difficult measures to remove hardware. The hardware must be removed prior to removing the polystyrene form and installing a metal grate.
U.S. Pat. No. 6,004,068 to Hosley, and issued Dec. 21, 1999, disclosed a second proposed solution. A corrugated form is assembled from several folding members and inserted into an excavated void. A plurality of U-shaped brackets are used to secure frame rails on either side of the form. However, the assembly is susceptible to deformation of the form or misalignment between opposing frames. Although the frames may stay in a parallel relationship to each other, they may xe2x80x9cparallelogramxe2x80x9d with respect to a longitudinal axis of the trench. In this condition, any support used to connect the rails would not be at a 90xc2x0 angle with each rail. Adjacent assembly sections may also be misaligned at joining points.
Alignment problems may be caused by human error during assembly. More frequently, misalignment is caused by the buoyancy forces imposed by the hardening material. Deformation of the form can result in an uneven bottom trench surface, adversely affecting liquid flow. Misalignment of frames can result in frames encased with portions above the surface of the concrete. This condition requires expensive rework when detected. If not detected, and the metal grates are installed, damaged to equipment or serious injury to personnel can result.
Certain applications, such as airports, require the installed metal grate to be secured with locking hardware. Misalignment between the rails causing the mounting hole location to move at small as xe2x85x9xe2x80x3 can prevent proper locking of the grates.
Ideally, a trench drain forming apparatus should be inexpensive to fabricate and potentially reusable. It should fold flat for easy and inexpensive transportation. Further, a trench drain forming apparatus should be easy to assemble ditch by relatively unskilled labor and install in the trench or void. The trench drain forming apparatus should be strong and stable to stay in place while the concrete is being poured and cured. Opposing frame rails should be held in proper alignment. The assembly should facilitate alignment between adjacent sections of the form so that the trench drain is continuous, without steps or ridges between form sections. The metal grate should be easily and safely lockable to the frame rails. Finally, the forming apparatus should facilitate easy removal after the concrete has dried or cured.
There is a need in the market for a method and apparatus for forming a trench drain offering the above discussed advantages.
The present invention is directed to method and apparatus for forming a trench drain offering improved stability and alignment.
In one embodiment, the apparatus for forming a trench drain includes an elongated trench form, first and second spaced apart frame rails, a support member removably affixed to the first and second frame rails and a first and second fastener.
The elongated trench form inserts into a trench along a longitudinal axis of the trench. The form is comprised of at least one folding member folded along predetermined lines to define a top surface, a bottom surface, and first and second spaced apart side surfaces.
The first and second spaced apart frame rails support the trench form. Each rail includes a horizontal portion, a transverse portion extending upwardly from the horizontal portion and a trench form engaging surface. The first frame rail abuts the first side surface of the form and the second frame rail abuts the second side surface of the form.
The support member is removably affixed to the first and second frame rails to maintain the first and second rails in a fixed position relative to each other. The support member includes a first opening extending through the support member adjacent one end of the support member and a first fastener bearing surface surrounding the first opening. The support member further includes a second opening extending through the support member adjacent an opposite end of the support member and a second fastener bearing surface surrounding the second opening. The first and second fastener bearing surfaces of the support member are spaced above respective uppermost surfaces of the transverse portions of the first and second frame rails.
The first fastener bears against the first fastener bearing surface of the support member, extends through the first opening of the support member and releasably engages the first frame rail. The second fastener bears against the second fastener bearing surface of the support member, extends through the second opening of the support member and releasably engages the second frame rail.
The trench form may include an outer form, a base form, a box form and a top form. The outer form has parallel first and second side walls defining the first and second side surfaces and a bottom wall defining the bottom surface. The base form is disposed in an interior region defined by the outer form. The box form is disposed in an interior region defined by the outer form and includes a plurality of cross members extending between the first and second side walls. The top form has a top wall defining the top surface.
The trench form may be made of corrugated cardboard. The predetermined lines may be weakened by scoring or perforation to facilitate folding. The trench form may include a wooden insert disposed between an upper surface of the box form and a lower surface of the top form.
The opposing edges of the top form may be folded in the shape of a square and disposed on respective trench form engaging surfaces of the first and second frame rails.
The first and second fasteners may include threaded studs which are threaded into respective threaded openings in the first and second frame rails and wing nuts which thread onto respective threaded studs and bear against respective first and second fastener bearing surfaces of the support member.
The top form may include slots through which upwardly extending tab portions of the first and second side walls protrude to releasably secure the top form to the outer form.
The support member may includes first and second vertically oriented cylindrical extensions sized to fit into corresponding first and second openings in the top form wherein the first and second openings of the support member extend through the cylindrical extensions.
The bottom wall of the outer form may be V-shaped resulting in a V-shaped bottom for the trench drain after hardening material has been poured in the trench and the trench form has been removed.
The first and second frame rails may include at least one extending leg having means for receiving an anchoring rod capable of being secured to ground defining the trench.
In an alternative embodiment, the apparatus for forming a trench drain includes first and second elongated trench forms, a first and second set of frame rails, a first and second cross member, a joint support member and a first and second fastener.
The first and second elongated trench forms insert into a trench. Each of the first and second forms include at least one folding member folded along predetermined lines to define a top surface, a bottom surface, and first and second spaced apart side surfaces. The first and second forms are positioned in longitudinal alignment to extend along a longitudinal axis of the trench.
The first set of frame rails includes first and second spaced apart frame rails to support the first trench form. Each rail includes a horizontal portion, a transverse portion extending upwardly from the horizontal portion and a trench form engaging surface. The first frame rail abuts the first side surface of the form and the second frame rail abuts the second side surface of the form;
The second set of frame rails includes third and fourth spaced apart frame rails to support the second trench form. Each rail comprising a horizontal portion, a transverse portion extending upwardly from the horizontal portion and a trench form engaging surface. The third frame rail abuts the first side surface of the form and the fourth frame rail abuts the second side surface of the form. The first and third frame rails are in alignment and the second and fourth frame rails are in alignment.
The first cross member is removably affixed to the first and second frame rails of the first set of frame rails to maintain the first and second rails in a fixed position relative to each other.
The second cross member is removably affixed to the third and fourth frame rails of the second set of frame rails to maintain the third and fourth rails in a fixed position relative to each other.
The joint support member is removably affixed to the first and fourth frame rails to maintain the first and fourth frame rails in a fixed position relative to each other. The support member includes a first opening extending through the support member adjacent one end of the support member and a first fastener bearing surface surrounding the first opening. The support member further includes a second opening extending through the support member adjacent an opposite end of the joint member and a second fastener bearing surface surrounding the second opening. The first and second fastener bearing surfaces of the joint member are spaced above respective uppermost surfaces of the transverse portions of the first and fourth frame rails.
The first fastener bears against the first fastener bearing surface of the joint support member, extends through the first opening of the joint support member, and releasably engages the first frame rail. The second fastener bears against the second fastener bearing surface of the joint support member, extends through the second opening of the joint support member, and releasably engages the fourth frame rail.
In a second alternative embodiment, the apparatus for forming a trench drain includes first and second elongated trench forms, a first and second set of frame rails, a first and second cross support member, a joint support member and a first, second, third, fourth, fifth and sixth fastener.
The first and second elongated trench forms insert into a trench. Each of the first and second forms include at least one folding member folded along predetermined lines to define a top surface, a bottom surface, and first and second spaced apart side surfaces. The first and second forms are positioned in longitudinal alignment to extend along a longitudinal axis of the trench.
The first set of frame rails includes first and second spaced apart frame rails to support the first trench form. Each rail includes a horizontal portion, a transverse portion extending upwardly from the horizontal portion and a trench form engaging surface. The first frame rail abuts the first side surface of the form and the second frame rail abuts the second side surface of the form.
The second set of frame rails includes third and fourth spaced apart frame rails to support the second trench form. Each rail includes a horizontal portion, a transverse portion extending upwardly from the horizontal portion and a trench form engaging surface. The third frame rail abuts the first side surface of the form and the fourth frame rail abuts the second side surface of the form. The first and third frame rails are in longitudinal alignment and the second and fourth frame rails are in longitudinal alignment.
The first cross support member is removably affixed to the first and second frame rails of the first set of frame rails to maintain the first and second rails in a fixed position relative to each other. The first support member includes a first opening extending through the support member adjacent one end of the support member and a first fastener bearing surface surrounding the first opening. The first support member further includes a second opening extending through the support member adjacent an opposite end of the support member and a second fastener bearing surface surrounding the second opening. The first and second fastener bearing surfaces of the support member are spaced above respective uppermost surfaces of the transverse portions of the first and second frame rails.
The first fastener bears against the first fastener bearing surface of the first cross support member, extends through the first opening of the support member, and releasably engages the first frame rail. The second fastener bears against the second fastener bearing surface of the first support member, extends through the second opening of the support member, and releasably engages the second frame rail.
The second cross support member is removably affixed to the third and fourth frame rails of the second set of frame rails to maintain the third and fourth rails in a fixed position relative to each other. The second support member includes a first opening extending through the support member adjacent one end of the support member and a first fastener bearing surface surrounding the first opening. The second support member further includes a second opening extending through the support member adjacent an opposite end of the support member and a second fastener bearing surface surrounding the second opening. The first and second fastener bearing surfaces of the support member are spaced above respective uppermost surfaces of the transverse portions of the third and fourth frame rails.
The third fastener bears against the first fastener bearing surface of the second cross support member, extends through the first opening of the support member, and releasably engages the third frame rail. The fourth fastener bears against the second fastener bearing surface of the second support member, extends through the second opening of the support member, and releasably engages the fourth frame rail.
The joint support member is removably affixed to the first and fourth frame rails to maintain the first and fourth frame rails in a fixed position relative to each other. The support member includes a first opening extending through the support member adjacent one end of the support member and a first fastener bearing surface surrounding the first opening. The support member further includes a second opening extending through the support member adjacent an opposite end of the support member and a second fastener bearing surface surrounding the second opening. The first and second fastener bearing surfaces of the support member are spaced above respective uppermost surfaces of the transverse portions of the first and fourth frame rails.
The fifth fastener bears against the first fastener bearing surface of the joint support member, extends through the first opening of the joint support member, and releasably engages the first frame rail. The sixth fastener bears against the second fastener bearing surface of the joint support member, extends through the second opening of the joint support member, and releasably engages the fourth frame rail.
A method of forming a trench drain includes the first step of forming a trench in the ground extending along a longitudinal axis. A second step includes assembling a trench form comprised of at least one folding member folded along predetermined lines.
A next step includes positioning a first set of frame rails so as to extend along the longitudinal axis of the trench and to engage and support the trench form. A next step includes positioning the trench form so as to engage and be supported by the first and second frame rails.
A next step includes providing a support member to releasably secure the first frame rail to the second frame rail to maintain the first and second rails in a fixed position relative to each other. The support member includes a first opening extending through the support member adjacent one end of the support member and a first fastener bearing surface surrounding the first opening. The support member further includes a second opening extending through the support member adjacent an opposite end of the support member and a second fastener bearing surface surrounding the second opening. The first and second fastener bearing surfaces of the support member are spaced above respective uppermost surfaces of the first and second frame rails.
A next method step includes securing the support member to the first and second frame rails by two intermediate steps. The first intermediate step includes fastening a first fastener between the support member and the first frame rail. The first fastener bears against the first fastener bearing surface of the support member, extends through the first opening of the support member, and releasably engages the first frame rail. The second intermediate step includes fastening a second fastener between the support member and the second frame rail. The second fastener bears against the second fastener bearing surface of the support member, extends through the second opening of the support member, and releasably engages the second frame rail.
A next step includes applying hardening compound into the trench in areas adjacent the first and second trench forms. A final step includes removing the first and second fasteners, the support member and the trench form.
An alternative method of forming a trench drain is also disclosed. The alternative method includes a first step of forming a trench in the ground extending along a longitudinal axis. A second step includes assembling first and second trench forms.
A step includes positioning a first and second frame rail in spaced apart relationship so as to extend along the longitudinal axis of the trench and to engage and support the first trench form.
A step includes positioning the first trench form so as to engage and be supported by the first and second frame rails.
A step includes positioning a third and fourth frame rail in spaced apart relationship so as to extend along the longitudinal axis of the trench and to engage and support the second trench form.
A step includes positioning the second trench form so as to engage and be supported by the third and fourth frame rails.
The next step includes providing a joint support member to releasably secure the first frame rail to the fourth frame rail. The joint support member is adapted to removably engage the first and fourth frame rails to maintain the first and fourth rails in a fixed position relative to each other. The joint support member includes a first opening extending through the cross support member adjacent one end of the support member and a first fastener bearing surface surrounding the first opening. The joint member further includes a second opening extending through the joint support member adjacent an opposite end of the support member and a second fastener bearing surface surrounding the second opening. The first and second fastener bearing surfaces of the cross support member are spaced above respective uppermost surfaces of transverse portions of the first and fourth frame rails.
A next method step includes securing the joint support member to the first and fourth frame rails by two intermediate steps. The first intermediate step includes fastening a first fastener between the joint support member and the first frame rail. The first fastener bears against the first fastener bearing surface of the cross support member, extends through the first opening of the cross support member, and releasably engages the first frame rail. The second intermediate step includes fastening a second fastener between the joint support member and the fourth frame rail. The second fastener bears against the second fastener bearing surface of the cross support member, extends through the second opening of the cross support member, and releasably engages the fourth frame rail.
A next step includes applying hardening compound into the trench in areas adjacent the first and second trench forms. A final step includes removing the first and second fasteners, the joint support member and the first and second trench forms.
These and other objects, advantages and features of the invention will become better understood from a detailed description of an exemplary embodiment of the invention which is described in conjunction with the accompanying drawings.